Dissertations / Theses on the topic 'Sodiium'
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VOILLEY, NICOLAS. "L'homeostasie du sodium : implication du canal sodique epithelial sensible a l'amiloride, identification moleculaire et regulation." Nice, 1995. http://www.theses.fr/1995NICE4866.
Full textAllache, Redouane. "Régulation du canal sodique épithélial sensible à l'amiloride par les sérine-protéases et le sodium extracellulaire." Mémoire, Université de Sherbrooke, 2007. http://hdl.handle.net/11143/5538.
Full textTremblay, Christina. "Caractérisation d'un canal sodique "de fuite" essentiel pour la détection do sodium dans les neurones MnPo." Master's thesis, Université Laval, 2009. http://hdl.handle.net/20.500.11794/20517.
Full textAllache, Redouane. "Régulation du canal sodique épithélial sensible à l'amiloride par les sérine-protéases et le sodium extracellulaire." [S.l. : s.n.], 2007.
Find full textTremblay, Christina. "CARACTÉRISATION D'UN CANAL SODIQUE « DE FUITE » ESSENTIEL POUR LA DÉTECTION DU SODIUM DANS LES NEURONES DU MNPO." Thesis, Université Laval, 2009. http://www.theses.ulaval.ca/2009/25956/25956.pdf.
Full textThompson, Laura M. "The depletion of nitric oxide by reaction with molten sodium carbonate and sodium carbonate/sodium sulfide mixtures." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/5797.
Full textPryce, Morris David Jonathan. "Sodium Ordering and the Control of Properties in Sodium Cobaltate." Thesis, University of Liverpool, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486940.
Full textWarrington, P. L. "Sodium-ceramic reactions." Thesis, University of Nottingham, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373344.
Full textNose, Masafumi. "Studies on Sodium-containing Transition Metal Phosphates for Sodium-ion Batteries." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215565.
Full textLee, Chi-Ming. "Pitting corrosion inhibition of mild steel by sodium molybdate and sodium silicate." Thesis, University of Nottingham, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292172.
Full textWu, Di Ph D. Massachusetts Institute of Technology. "A layered sodium titanate as promising anode material for sodium ion batteries." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/93004.
Full textCataloged from PDF version of thesis.
Includes bibliographical references (pages 58-60).
Sodium ion batteries have recently received great attention for large-scale energy applications because of the abundance and low cost of sodium source. Although some cathode materials with desirable electrochemical properties have been proposed, it's quite challenging to develop suitable anode materials with high energy density and good cyclability for sodium ion batteries. Herein, we report a layered material, 03-NaTiO2, that delivers 130mAhg-1 of reversible capacity and presents excellent cyclability with capacity retention over 97.5% after 40 cycles and high rate capability. Furthermore, by coupling the electrochemical process with in situ X-ray diffraction, the structure evolution and variation of cell parameters corresponding to an 03-03' phase transition during sodium deintercalation is investigated. Unusual lattice parameter variation was observed by in situ XRD, which can be related to the structure modulation with varying Na vacancy ordering. An irreversible structural modification upon overcharging is also confirmed by in situ XRD. In summary, our work demonstrates that 03-NaTiO2 is a very promising anode material for sodium ion batteries with high energy density.
by Di Wu.
S.M.
Carnevali, Sofia. "Unsteady aspects of sodium-water reaction : water cleaning of sodium containing equipments." Compiègne, 2012. http://www.theses.fr/2012COMP2034.
Full textSodium fast Reactor (FSR) is one of the most promising nuclear reactor concepts in the frame of Generation IV systems to be commercialised in the next decades. One important safety issue about this technology is the highly exothermal chemical reaction of sodium when brought in contact with liquid water. This situation is likely, in particular during decommissioning, when sodium needs to be firstly converted (‘destroyed’) into non reactive species. This is achieved by water washing : the major products are then gaseous hydrogen and corrosive soda. Today, such operations are performed in confined chambers to mitigate the consequences of any possible abnormal conditions. It has for long been believed that the main safety problem was the combustion of hydrogen in the surrounding air despite some pioneering works suggested that even without air the reaction could be explosive. It is extremely important to clarify the phenomenology of sodium-water interactions since available knowledge does not allow a robust extrapolation of existing data/model to full scale plants. The primary objective of this work is to identify and assess the details of the phenomenology, especially at the sodium/water interface, to isolate the leading mechanisms and to propose a robust and innovative modelling approach. A large body of yet unreleased experimental data extracted from the files of the French Commissariat à l’Energie Atomique (CEA) was collated and analysed on the basis of “explosion” physics. Some additional experiments were also performed to fill some gaps, especially about the kinetics of the reaction. The results strongly suggest that the fast expansion of gas producing a blast wave in certain conditions is a kind of vapour explosion. It also appears that any potential hydrogen-air explosion should be strongly mitigated by the large quantity of water vapour emanating also from the reaction zone. The limitations of existing modelling approaches are clearly identified and alternatives are proposed and offer a better perspective of extrapolation to full scale installations
Wester, Leanna E. "Offering sodium bentonite and sodium bicarbonate free-choice to lactating dairy cattle." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/34899.
Full textMaster of Science
Webster, Alison Lynn. "Knowledge, Attitudes, and Practices Regarding Dietary Sodium Intake, and Associations with Sodium Consumption and Blood Pressure in College Students." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1500548039026394.
Full textRaab, Eric Lowell. "Trapping sodium with light." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/118103.
Full textSimone, Virginie. "Développement d'accumulateurs sodium-ion." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAI092/document.
Full textBecause of the development of renewable energy and electric vehicles, the need for a large scale energy storage has increased. This type of storage requires a large amount of raw materials. Therefore low cost and abundant resources are necessary. Consequently the use of sodium batteries is of interest because sodium’s low cost, high abundance, and worldwide availability. This PhD thesis deals with the study of a full Na-ion cell containing a hard carbon negative electrode, and a layered oxide positive electrode. A shorter part concerns the electrolyte.Concerning the negative electrode, the first objective was to understand in detail the influence of the pyrolysis temperature of a hard carbon precursor, cellulose, on the final structure of the material and its consequences on the electrochemical performance. Many techniques were used to characterize the hard carbon structure as a function of the pyrolysis temperature. Localized graphitization, pore closure, and an increase in micropore size have been observed with increasing temperature. The best electrochemical performance has been reached with the hard carbon synthesized at 1600°C: a reversible capacity of around 300 mAh.g-1 stable over 200 cycles is obtained at 37.2 mA.g-1 with an initial coulombic efficiency of 84%. To deeper understand sodium insertion mechanisms in hard carbon structures impedance spectroscopy, SAXS and EDX were carried out on hard carbon electrodes cycled at different voltages.The layered oxide Na0.6Ni0.25Mn0.75O2 was investigated as the positive electrode. It was observed that with increasing calcination temperature the number of P3-type stacking faults decreases in favor of a more crystalline P2 phase. Then, the carbonate-based electrolyte has been optimized to guarantee the reproducibility of the electrochemical tests performed in a layered oxide//sodium metal configuration. A first oxidation capacity of around 130 mAh.g-1 is reached. However this value drops quickly after 40 cycles. Operando XRD analysis did partially explain the capacity decrease. Finally, the results of these investigations were used to design an optimized full cell which demonstrated promising performance during initial testing
Collet, Pascal. "Le fluorure de sodium." Paris 5, 1988. http://www.theses.fr/1988PA05P015.
Full textSohraby, Sarah. "Le canal sodium épithélial." Doctoral thesis, Universite Libre de Bruxelles, 1988. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/213399.
Full textRobinet, Laurianne. "Le rôle des polluants organiques dans l'altération des verres sodiques historiques." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2006. http://tel.archives-ouvertes.fr/tel-00088408.
Full textScott, Leonard Lindsay. "Electrolytic manufacture of thiosulfate-free solutions of sodium hydrosulfite from aqueous sodium bisulfite." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/10241.
Full textMacLeod, Mary Joan. "Sodium-lithium countertransport, sodium-hydrogen exchange and membrane microviscosity in patients with hyperlipidaemia." Thesis, University of Glasgow, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300735.
Full textSchindler, Manon. "Deracémisation du chlorate de sodium avec et sans l’influence du dithionate de sodium." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMR004.
Full textIn the field of pharmaceutical chemistry, crystallization based methods are used to obtain pure enantiomers. The advantage of deracemization is the conversion of the unwanted enantiomer into the desired enantiomer by means of racemization in liquid phase, giving rise to a theoretical yield of 100%. The mechanism of Temperature Cycling Induced Deracemization (TCID) process, still matter of debate, has been investigated in this thesis. Research was focused on the development of the TCID process for sodium chlorate (NaClO3). This model compound is achiral at the solvated state which enables to focus investigation on crystallization mechanisms involved during deracemization. After the full solid state characterization of sodium dithionate (Na2S2O6), this compound has been used as a nonchiral impurity in the TCID process of NaClO3 and highlighted the key role of secondary nucleation in the process. Thus, the success of the TCID process depends on the right balance between growth and secondary nucleation. From an industrial perspective, the Couette Taylor reactor has been considered as a promising device for the development of continuous deracemization process. Attempts to deracemize NaClO3 in this kind of reactor showed that symmetry breaking and deracemization of NaClO3 were successful. Nonetheless, crystal recycling, via either attrition or secondary nucleation, has to be improved to enhance deracemization process before considering the execution of continuous process
Chassery, Aurélien. "Étude expérimentale et modélisation phénoménologique de l’hydrolyse de sodium tritié : influence des conditions opératoires sur la distribution du tritium dans les effluents." Phd thesis, Toulouse, INPT, 2014. http://oatao.univ-toulouse.fr/13934/1/chassery.pdf.
Full textShawk, Dwight Jay. "Effects of sodium, chloride, and sodium metabisulfite in nursery and grow-finish pig diets." Thesis, Kansas State University, 2018. http://hdl.handle.net/2097/38659.
Full textDepartment of Animal Sciences and Industry
Robert D. Goodband
Michael D. Tokach
A total of 12,229 pigs were used in nine experiments to determine the effects of Na, Cl, and sodium metabisulfite-based feed additives on pig growth performance. Experiments 1, 2, and 3 were conducted to determine the effects of added dietary salt on growth performance of pigs weighing 7 to 10, 11 to 30, and 27 to 65 kg. The BLL models suggested the optimal dietary added salt concentration to maximize ADG for pigs weighing 7 to 10 and 11 to 30 kg was 0.59% (0.34% Na and 0.58% Cl) and 0.51% added salt (0.22% Na and 0.42% Cl), respectively. There was no evidence to indicate that growth of 27 to 65 kg pigs was improved beyond a 0.10% added salt inclusion (0.11% Na and 0.26% Cl). Experiments 4, 5, and 6 were conducted to determine the effects of source and concentration of Na and Cl on the growth performance of pigs weighing 7 to 12 kg. In Exp. 4, pigs fed an added salt diet that contains a Na and Cl concentration of 0.35% and 0.60% had greater growth performance compared to pigs fed a deficient Na concentration of 0.18%. In Exp. 5, pigs fed a Na concentration of 0.35%, regardless of ion source, had improved ADG compared to pigs fed a Na concentration of 0.13% or 0.57%. In Exp. 6, maximum ADG and G:F could be obtained with a Cl concentration of 0.38% based on the BLL and QP models. Experiments 7, 8, and 9 were conducted to evaluate the effects of Product 1 (Provimi, Brooksville, OH), Product 2 (Nutriquest, Mason City, IA), and sodium metabisulfite (SMB) on the growth performance of nursery pigs weighing approximately 6 to 25 kg. In Exp. 7, pigs fed Product 1 had higher ADG compared to pigs fed the control. In Exp. 8, pigs fed either Product 1 or 2 at the highest concentration and for the longest period of time had greater ADG compared to pigs fed the control diet. In Exp. 9, pigs fed SMB or Product 1 had greater ADG compared to pigs fed a lower concentration of SMB and the control.
Shaikh, Amjad A. "Conversion of sodium carbohydrate to sodium carbonate monohydrate in an inclined horizontal rotating cylinder." Thesis, University of Sheffield, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444877.
Full textBallaminut, Carlos Eduardo Carneiro. "Seletividade da cultura do algodoeiro aos herbicidas Diuron, Clomazone, Trifloxysulfuron-sodium e Pyrithiobac-sodium." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/11/11136/tde-14122009-144354/.
Full textThe use of herbicides for weed chemical management is one of the most efficient methods used nowadays. However, herbicides considered selective to the crop can cause some problems to the vegetative development or to the final yield. This way, the study aimed to evaluate the effect of four of the main herbicides used in the cotton crop, two of them used as pre-emergent of the crop and weeds (Clomazone and Diuron) and two used as post-emergent of the crop and weeds (Trifloxysulfuron-sodium e Pyrithiobac-sodium) in the varieties Fibermax 966, DeltaOpal and Aroeira, the main varieties commercially grown, with low, medium and high vegetative development. The experimental design used was the randomized blocks, with 4 replications. Each one of the blocks had 9 sup-plots to each variety, with a final number of 36 sub-plots. In the subplots of each variety there were 8 herbicides treatments plus the control treatment, this one left without weed interference along all the crop development, using manual weed control. The main features evaluated were plants height, Leaf Area Index (LAI), dry matter, yield, balls weight, seed germination and fiber quality. For both, the pre-emergent herbicide treatments, and postemergent treatments, there were injuries in the cotton plants, mainly to the treatments with highest doses (Diuron 2,0 kg ia/ha, Clomazone 600 g ia/ha, Trifloxysulfuron-sodium 7.5g ia g/ha and Pyrithiobac-sodium 140g ia/ha), however, these injuries were temporary and were not present in future evaluations. Regarding the effect of the injuries to the vegetative development, the cultivar Fibermax 966 showed Leaf Area Index and dry matter reduction in the post-emergent treatments, both in the second evaluation to the treatments in the highest dose. This decrease in plant development did not impact final yield, balls weight, seed germination or fiber quality. To the other varieties, the post-emergent herbicide treatments did not lead any vegetative development reduction when compared to the control treatment, neither to the final characteristics as yield, fiber quality and seed germination. Para os tratamentos herbicidas em pré-emergência, o herbicida Diuron na maior dose causou as maiores cloroses nas cultivares analisadas, além de levar a um menor acúmulo de massa seca e produtividade final para a cultivar Aroeira, quando comparada ao tratamento com Clomazone. Para as demais cultivares, não foram verificados quaisquer efeitos em relação ao desenvolvimento vegetativo, produtividade final ou qualidade da fibra produzida. For the pre-emergent herbicide treatments, Diuron in the highest dose caused greater damage to the different materials, leading to dry matter reduction and final yield for the cultivar Aroeira, when compared to the Clomazone treatment. For the other cultivars, the treatment did not present any effects in plants development, final yield or fiber quality.
Plantier, Vanessa. "La spasticité après lésion de la moelle épinière : Identification des mécanismes moléculaires et ioniques sous-jacents." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM5059.
Full textSpasticity is commonly caused by several pathologies and specifically after a spinal cord injury (SCI). Spasticity is usually associated with hypertonia, clonus, muscle spasm and pain. The present thesis aims to identify the upstream mechanism in the pathophysiology of spasticity Calpain, a calcium-activated cysteine protease, has been shown to participate in the development of the inflammatory processes after SCI. Of special interest, some determinants governing the inactivation of sodium (Na+) channels are sensitive to proteases and their proteolytic cleavage prevents inactivation of Na+ channels. As a result, INaP is strongly increased. It is worth mentioning that the C-terminal domain of KCC2 is also sensitive to proteases which alter KCC2 ability to extrude Cl- ions. Among the different proteases, calpains are able to truncate both Na+ channels and KCC2 transporters. This led us to consider the exciting possibility that a proteolytic cleavage of both Na+ channels and KCC2 by calpains could compose an upstream inflammatory mechanism contributing to the development of spasticity after SCI. My thesis demonstrates that the cleavage of Na+ channels and KCC2 by calpain after SCI, is responsible for the upregulation of INaP and disinhibition of motoneurons, that both act synergistically to generate spasticity. Calpain inhibition by MDL28170 reduced the cleavage of both Na+channels and KCC2 associated with a respective downregulation of INaP, hyperpolarizing shift of the EIPSP, and an alleviation of spasticity. The thesis represents a significant breakthrough by opening novel perspectives to develop therapies
Frauendorf, Stefan, M. Brack, and S. M. Reimann. "Triaxial shapes of sodium clusters." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-32199.
Full textDavis, Samuel M. "Electrochemical Splitting of Sodium Sulfate." Thesis, Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/11505.
Full textGreet, P. A. "Observations on the sodium airglow /." Title page, contents and abstract only, 1988. http://web4.library.adelaide.edu.au/theses/09PH/09phg8166.pdf.
Full textLoukas, Andrew. "Sodium channel mutations causing epilepsy." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80321.
Full textThe C121W mutation causes a 100 fold reduction in efficacy of current modulation as well as a reduction of current amplitude. This may cause increased sodium currents via a negative shift of the steady-state inactivation curve. alpha-D188V channels recover faster from the inactivated state which causes a resistance to frequency-dependent cumulative inactivation of current amplitude. This may contribute to cellular hyperexcitability resulting in ictal events in the epileptic patient.
Moore, D. R. "Carbon transfer in liquid sodium." Thesis, University of Nottingham, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371130.
Full textKennedy, P. A. "Chemistry of sodium-caesium solutions." Thesis, University of Nottingham, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355439.
Full textBlake, S. M. "Physicochemical studies on sodium hyaluronate." Thesis, University of Salford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381670.
Full textRichards, Robert. "The pharmacokinetics of sodium cromoglycate." Thesis, University of Southampton, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359034.
Full textDavis, Kendall Bruce. "Evaporative cooling of sodium atoms." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/11384.
Full textSchneider, Nicholas McCord. "Sodium in Io's extended atmosphere." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184408.
Full textChiu, N. X. N. "Designing microstructures for sodium reduction." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/33595/.
Full textFrauendorf, Stefan, M. Brack, and S. M. Reimann. "Triaxial shapes of sodium clusters." Forschungszentrum Rossendorf, 1995. https://hzdr.qucosa.de/id/qucosa%3A22046.
Full textBossuyt, Julie. "Sodium-calcium exchange and caveolins." MU has:, 2002. http://wwwlib.umi.com/cr/mo/fulltext?p3052149.
Full textLi, Wei. "Coal desulfurization with sodium hypochlorite." Morgantown, W. Va. : [West Virginia University Libraries], 2004. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3546.
Full textTitle from document title page. Document formatted into pages; contains vii, 32 p. : ill. Includes abstract. Includes bibliographical references (p. 32).
Naqash, Sahir Verfasser], Olivier [Akademischer Betreuer] Guillon, and Jochen M. [Akademischer Betreuer] [Schneider. "Sodium ion conducting ceramics for sodium ion batteries / Sahir Naqash ; Olivier Guillon, Jochen Michael Schneider." Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://d-nb.info/1190040611/34.
Full textBolton, Lesley Margaret. "Erythrocyte sodium content and sodium pump kinetics in the puerperium following normal and hypertensive pregnancy." Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283055.
Full textNaqash, Sahir [Verfasser], Olivier Akademischer Betreuer] Guillon, and Jochen M. [Akademischer Betreuer] [Schneider. "Sodium ion conducting ceramics for sodium ion batteries / Sahir Naqash ; Olivier Guillon, Jochen Michael Schneider." Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://nbn-resolving.de/urn:nbn:de:101:1-2019070807164971884045.
Full textVivaldi, Daniele. "Modeling of underexpanded reactive CO2-into-sodium jets, in the frame of sodium fast reactors." Thesis, Saint-Etienne, EMSE, 2013. http://www.theses.fr/2013EMSE0707/document.
Full textThis PhD work was motivated by the investigations in the frame of supercritical CO2 Brayton cycles as possible energy conversion cycles for the Sodium-cooled Fast nuclear Reactors (SFRs). Following an accidental leakage inside the sodium-CO2 heat exchanger of a SFR, the CO2, having an operating pressure of about 200 bars, would be injected into the low-operatingpressure liquid sodium, creating an underexpanded reactive CO2-into-sodium jet. The goal of this PhD work is the development of a numerical model of the two-phase reactive CO2-into-sodium jet.A numerical model of an underexpanded non-reactive gas-into-liquid jet was developed, adopting a 3D unsteady multi-fluid CFD approach. The numerical results have been validated through the experimental results obtained with a facility employing optical probe technique. A numerical model for the chemical reaction between sodium and CO2 was then developed and integrated into the 3D two-fluid model. The resulting model allows to determine the temperature profiles inside the reactive jet and on the heat exchanger tubes
Cesetti, Lorenzo. "Systematic study of in-situ sodium plating/stripping on anode free substrates for sodium ion batteries." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
Find full textStöver, Harald D. H. "Sodium binding to crown ether derivatives bulk membrane transport and sodium-23 nuclear magnetic resonance studies." Thesis, University of Ottawa (Canada), 1986. http://hdl.handle.net/10393/5211.
Full textBelhimer, E. "Stress corrosion cracking of pipeline steels and pure iron in a sodium carbonate-sodium bicarbonate solution." Thesis, University of Newcastle Upon Tyne, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376310.
Full textArmellini, Fred J. "Phase equilibria and precipitation phenomena of sodium chloride and sodium sulfate in sub- and supercritical water." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/12552.
Full textVanderhaegen, Matthias. "Modélisation du bruit acoustique d'ébullition du sodium lors des bouchages d'assemblage dans les réacteurs au sodium." Paris 7, 2013. http://www.theses.fr/2013PA077170.
Full textIn the framework of the fourth generation of nuclear reactors safety requirements, the acous¬tic boiling detection is studied to detect subassembly blockages. Boiling, that might occur during subassembly blockages and that can lead to clad failure, génerates hydrodynamic noise that can be related to the two-phase flow. A bubble dynamics study shows that the sound source during subassembly boiling is condensation. This particular phenomenon generates most noise as a high subcooling is present in the subassembly and because of the high thermal diffusivity of sodium. This result leads to an estimate of the form of the acous¬tic spectrum that will be filtered and amplified during propagation inside the liquid. And even though it is unlikely that bubbles will be present inside the subassembly, due to the very graduai temperature profile at the wall and due to the geometry that leads to a strong confinement of the vapor, the historical bubble dynamics approach gives some insight in previous measurements. Additionnaly, some hypotheses can be disproved. These theoretical ideas are validated with a small water experiment, yet it also shows that a simple experience in sodium doesn't lead to a better knowledge of the acoustic source. A theoretical analysis also revealed that a realistic experiment with a simulant fluid, such as water or mercury, isn't representative. A similar conclusion is obtained when study¬ing cavitation as a simulant acoustic source. As such, the acoustic detection of boiling, in comparison with other detection systems, isn't sufficiently developed yet to be applied as a reactor protective system